Oracle查看sql执行计划和统计信息-mysql教程

--获取sql的执行计划以及统计信息，不显示查询信息 SQLgt; set autotrace traceonly;SQLgt; select * from test;执行计划-----

首页 → 数据库技术

背景：

Oracle查看sql执行计划和统计信息

[日期：2011-08-31] 来源：Linux社区 作者：AnyJack [字体：]

--获取sql的执行计划以及统计信息，不显示查询信息
SQL> set autotrace traceonly;
SQL> select * from test;
执行计划
----------------------------------------------------------
Plan hash value: 1357081020
--------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
--------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 2 | 130 | 3 (0)| 00:00:01 |
| 1 | TABLE ACCESS FULL| TEST | 2 | 130 | 3 (0)| 00:00:01 |
--------------------------------------------------------------------------
Note
-----
- dynamic sampling used for this statement
统计信息
----------------------------------------------------------
0 recursive calls
0 db block gets
8 consistent gets
6 physical reads
0 redo size
523 bytes sent via SQL*Net to client
416 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
2 rows processed
==============================================================
--只显示统计信息
SQL> set autot traceonly stat;
SQL> select * from test;
统计信息
----------------------------------------------------------
0 recursive calls
0 db block gets
8 consistent gets
0 physical reads
0 redo size
523 bytes sent via SQL*Net to client
416 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
2 rows processed
==============================================================
--只显示执行计划
SQL> set autot traceonly exp;
SQL> select * from test;
执行计划
----------------------------------------------------------
Plan hash value: 1357081020
--------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
--------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 2 | 130 | 3 (0)| 00:00:01 |
| 1 | TABLE ACCESS FULL| TEST | 2 | 130 | 3 (0)| 00:00:01 |
--------------------------------------------------------------------------
Note
-----
- dynamic sampling used for this statement
==============================================================
--开启sql跟踪,显示查询结果和执行计划，以及统计信息
SQL> set autot on;
SQL> select * from test;
T_ID T_NAME
-------------------------------------------------------------------------------------
1 t1
2 t2
执行计划
----------------------------------------------------------
Plan hash value: 1357081020
--------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
--------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 2 | 130 | 3 (0)| 00:00:01 |
| 1 | TABLE ACCESS FULL| TEST | 2 | 130 | 3 (0)| 00:00:01 |
--------------------------------------------------------------------------
Note
-----
- dynamic sampling used for this statement
统计信息
----------------------------------------------------------
0 recursive calls
0 db block gets
8 consistent gets
0 physical reads
0 redo size
523 bytes sent via SQL*Net to client
416 bytes received via SQL*Net from client
2 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
2 rows processed
==============================================================
--关闭sql跟踪,只显示查询结果
SQL> set autot off;
SQL> select * from test;
T_ID T_NAME
-------------------------------------------------------
1 t1
2 t2

用SAS宏实现Oracle中的decode函数

Oracle RMAN 丢失归档日志：ORA-19625: error identifying file

相关资讯 Oracle教程

图片资讯

本文评论 　　查看全部评论 (0)

评论声明

最新资讯

本周热门